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When planning or simulating the operations of radio patrol cars, it is necessary to know the response time and response speed. In the present work the response speed was measured for downtown and surburban cars in order to facilitate computer simulations of patrol operations. Recorders were installed in the cars and records of dispatch delay, travel time, distance, response time, service time, and percentage of time per shift answering calls, were kept. Curves (which may be of general application) were fitted to the data for each parameter. The most probable average speed of the downtown car was 16 mph and of the suburban cars, 25 mph and 27 mph. Because of different average distances, however, the response times were comparable. Good agreement was found berween average travel times calculated from a formula given by R.C. Larson and travel times found experimentally in the present work. 相似文献
293.
A. T. J. Matthews Ellaleen C. Williams Jerome Laulicht Russell B. Donnelly Irene Nordine Henry C. Lajewski Paul F. Peifer Gustave A. de Cocq Joseph E. Russo Martin L. Hoffman J. Walter Cobb Worthington Miner Charles H. Adair G. Kerry Smith Eugene P. Schwartz R. L. Meier David B. Booth 《Society》1964,1(5):2-2
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Rost KT 《Journal of health law》2002,35(1):145-169
This article, winner of the 2000-2001 American Health Lawyers' Student Writing Competition, examines the conflicting policy goals at the heart of managed care--particularly in the use of financial incentives for physicians who limit their use of referrals and expensive diagnostic tests. While conceding the legality of such incentives, the author contends that Managed Care Organizations (MCOs) have a legal duty to disclose their existence to beneficiaries. After analyzing the basis for imposing a duty to disclose, the author proceeds to examine such issues as the proper timing, level, and extent of disclosure. 相似文献
298.
The forensic community continues to seek improvements in DNA typing methods on aspects such as sensitivity and efficacy. Reducing the volume of the AmpFlSTR Profiler Plus reagents offered greater sensitivity and improved the chance of obtaining useful results for samples with very low quantities of DNA and multiple source samples. On the downside, amplifications initiated with less than 0.4 ng of DNA exhibited a twofold increase in the standard deviation of peak ratios. This research suggested a twofold approach to analyzing samples. For samples with greater than 0.25 ng of DNA, a 25 microL reaction is appropriate. Samples that did not demonstrate quantifiable results, or that have less than 0.25 ng, can be amplified by drying the sample directly in the PCR tube and amplifying in a 5 microL reaction. The analyst can expect at least limited results with as little as 0.03 ng of DNA in the 5 microL reaction. 相似文献
299.
A rapid postmortem cardiac troponin T assay: laboratory evidence of sudden cardiac death 总被引:1,自引:0,他引:1
Cina SJ Brown DK Smialek JE Collins KA 《The American journal of forensic medicine and pathology》2001,22(2):173-176
Postmortem examination may be useful in establishing the cause of sudden unexpected death. In many instances, however, limitations of staffing, budget, and time may force the pathologist to triage cases to external examination rather than autopsy. A rapid assay for cardiac troponin T (cTnT) to document suspected cardiac-related deaths may optimize the use of the time and resources of the autopsy pathologist. Peripheral blood was sampled percutaneously before each of 40 autopsies and placed in the well of the Cardiac T Rapid Assay unit in accordance with the included instructions, and the results were read after 15 minutes. The assay result, decedent age, postmortem interval, and evidence of cardiopulmonary resuscitation were tabulated and subsequently correlated with the cause of death. On final sign-out of each of the autopsies, the cause of death was determined to be cardiac-related (n = 20) versus the cause in non-cardiac control subjects (n = 20). This determination was made while the investigators were blinded to the cTnT assay result. Of the 20 cardiac deaths, 17 (85%) showed positive results for cTnT compared with 6 (30%) false-positive results among the 20 control cases; this result was statistically significant according to the chi-square test. In the over-50 age group, the sensitivity of this assay in detecting cardiac-related death was 91%, with a specificity of 86%. Perimortem cardiopulmonary resuscitation did not appear to result in false-positive results. In the appropriate setting, this rapid assay for cTnT can provide valuable data supportive of a cardiac-related death. This inexpensive test may best be used in triaging sudden deaths in persons over 50 to external examination versus complete autopsy. 相似文献
300.
Primary Attachment to Parents and Peers during Adolescence: Differences by Attachment Style 总被引:5,自引:0,他引:5
This study examines the nature of adolescent attachment to parents and peers during adolescence. A projective measure was used to classify 99 11th and 12th grade students into secure, insecure dismissing, and insecure preoccupied attachment groups. Respondents identified their primary attachment figure by nomination and by rating the level of attachment support they received from mothers, fathers, best friends, and boy/girlfriends. On average, parents and peers were equally likely to be identified as primary attachment figures but individual preference was strongly tied to attachment style. Secure adolescents significantly favored mothers over best friends, boy/girlfriends, and fathers. Although secure adolescents with romantic partners rated mothers lower on attachment support, none of the adolescents from this group nominated a boy/girlfriend as their primary attachment figure. In contrast insecure adolescents indicated a strong preference for boy/girlfriends and best friends as their primary target for attachment and nearly a third of dismissing adolescents identified themselves as their primary attachment figure. Findings are discussed in terms of individual differences in attachment during adolescence. 相似文献